Evaluating transport user benefits and social surplus in a transport market--The case of the Norwegian ferries

The article first infers how consumer surplus in a market is linked to revenue under different assumptions about fare elasticity and when using different types of demand functions. This information is added to producer surplus in order to derive social surplus. The method, thus, produces a simple approach for authorities to assess social surplus in a market and its benefits to the users. A modified exponential demand function is applied to calculate consumer surplus and social surplus for 97 ferry services in Norway regulated by the state. The calculations are based on empirical data concerning ferry fare, revenue data at service level and reasonable assumptions about fare point elasticity for services covering different distances. In 2007, these services generated welfare for the users (consumer surplus) and the society (social surplus) amounting to about 5.8 billion NOK and 4.3 billion NOK, respectively. Consumer surplus and social surplus varied considerably amongst the services. Only 3 of the 97 services operate with positive profits and, hence, without subsidies. About 21 of the services contribute negatively to social surplus. Many of these unprofitable services are the only transport alternatives in rural areas and could be argued to continue operation according to politically decided regional measures. Implicitly, maintaining all these 21 services means that the welfare for the people in these areas is valued as up to four times greater than the welfare of the people in the rest of society.